Journal of Materials Science, Vol.51, No.11, 5556-5564, 2016
Membranes for rechargeable lithium sulphur semi-flow batteries
The aim of achieving high-energy, long-life, safe and low cast storage batteries has brought tremendous scientific attention in the last decade, resulting in significant improvements in the stored energy of cathodes and anodes particularly in lithium-based battery technology. However, presently available lithium-ion technology cannot satisfy the increasing demand for energy density. Li-S battery is a typical example, which can offer theoretically a fivefold increase in energy density compared with conventional lithium rechargeable batteries. Despite significant advances, there are challenges to its wide-scale implementation, which include dissolution of intermediate polysulphide reaction species into the electrolyte when liquid polysulphide is used as cathodes. Another problem is preparation of polysulphides. Here we report a novel approach to replace the liquid electrolyte with solid lithium conducting membranes, Argyrodite (Li6PS5X(X = Cl,Br)) and Li10GeP2S12 solid electrolytes to mitigate the problem. Among the three solid electrolyte membranes Li10GeP2S12 exhibited high first discharge specific capacity of 1435 (+/- 3) mAh g(-1) at 0.5 C rate.